Wide Detection Range Flexible Pressure Sensors Based on 3D Interlocking Structure TPU/ZnO NWs

The high sensitivity and wide linear sensing range are two crucial performance parameters for pressure sensors. This paper presents a flexible pressure sensor based on a 3D interlocking structure resembling the biomimetic dog-tail grass. The 3D interlocking structure of TPU/ZnO nanowires (NWs) uniformly increases with the applied pressure, resulting in a proportional increase in the contact area. Simultaneously, ZnO NWs form an upper sparse and lower dense structure on the TPU skeleton, enabling it to withstand exceptionally high pressures. Leveraging these advantages, the flexible pressure sensor exhibits elevated sensitivity (29.7 kPa-1) and an ultra-wide linear sensing range (up to 2250 kPa), representing a significant improvement compared to prior research. The sensor demonstrates outstanding performance in terms of repeatability and stability. Furthermore, applications in wearable electronic devices and pixel analysis in pressure array configurations are demonstrated, showcasing high performance achieved through straightforward and cost-effective fabrication methods, thereby offering a promising strategy for future developments in flexible electronic devices.